1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
|
package org.postgresql.jdbc1;
// IMPORTANT NOTE: This file implements the JDBC 1 version of the driver.
// If you make any modifications to this file, you must make sure that the
// changes are also made (if relevent) to the related JDBC 2 class in the
// org.postgresql.jdbc2 package.
import java.sql.*;
import org.postgresql.util.PSQLException;
/*
* A Statement object is used for executing a static SQL statement and
* obtaining the results produced by it.
*
* <p>Only one ResultSet per Statement can be open at any point in time.
* Therefore, if the reading of one ResultSet is interleaved with the
* reading of another, each must have been generated by different
* Statements. All statement execute methods implicitly close a
* statement's current ResultSet if an open one exists.
*
* @see java.sql.Statement
* @see ResultSet
*/
public class Statement extends org.postgresql.Statement implements java.sql.Statement
{
private Connection connection; // The connection who created us
/*
* Constructor for a Statement. It simply sets the connection
* that created us.
*
* @param c the Connection instantation that creates us
*/
public Statement (Connection c)
{
connection = c;
}
/*
* Execute a SQL statement that retruns a single ResultSet
*
* @param sql typically a static SQL SELECT statement
* @return a ResulSet that contains the data produced by the query
* @exception SQLException if a database access error occurs
*/
public java.sql.ResultSet executeQuery(String sql) throws SQLException
{
this.execute(sql);
while (result != null && !((org.postgresql.ResultSet)result).reallyResultSet())
result = ((org.postgresql.ResultSet)result).getNext();
if (result == null)
throw new PSQLException("postgresql.stat.noresult");
return result;
}
/*
* Execute a SQL INSERT, UPDATE or DELETE statement. In addition
* SQL statements that return nothing such as SQL DDL statements
* can be executed
*
* @param sql a SQL statement
* @return either a row count, or 0 for SQL commands
* @exception SQLException if a database access error occurs
*/
public int executeUpdate(String sql) throws SQLException
{
this.execute(sql);
if (((org.postgresql.ResultSet)result).reallyResultSet())
throw new PSQLException("postgresql.stat.result");
return this.getUpdateCount();
}
/*
* setCursorName defines the SQL cursor name that will be used by
* subsequent execute methods. This name can then be used in SQL
* positioned update/delete statements to identify the current row
* in the ResultSet generated by this statement. If a database
* doesn't support positioned update/delete, this method is a
* no-op.
*
* <p><B>Note:</B> By definition, positioned update/delete execution
* must be done by a different Statement than the one which
* generated the ResultSet being used for positioning. Also, cursor
* names must be unique within a Connection.
*
* <p>We throw an additional constriction. There can only be one
* cursor active at any one time.
*
* @param name the new cursor name
* @exception SQLException if a database access error occurs
*/
public void setCursorName(String name) throws SQLException
{
connection.setCursorName(name);
}
/*
* Execute a SQL statement that may return multiple results. We
* don't have to worry about this since we do not support multiple
* ResultSets. You can use getResultSet or getUpdateCount to
* retrieve the result.
*
* @param sql any SQL statement
* @return true if the next result is a ResulSet, false if it is
* an update count or there are no more results
* @exception SQLException if a database access error occurs
*/
public boolean execute(String sql) throws SQLException
{
if (escapeProcessing)
sql = escapeSQL(sql);
result = connection.ExecSQL(sql);
return (result != null && ((org.postgresql.ResultSet)result).reallyResultSet());
}
/*
* getUpdateCount returns the current result as an update count,
* if the result is a ResultSet or there are no more results, -1
* is returned. It should only be called once per result.
*
* @return the current result as an update count.
* @exception SQLException if a database access error occurs
*/
public int getUpdateCount() throws SQLException
{
if (result == null)
return -1;
if (((org.postgresql.ResultSet)result).reallyResultSet())
return -1;
return ((org.postgresql.ResultSet)result).getResultCount();
}
/*
* getMoreResults moves to a Statement's next result. If it returns
* true, this result is a ResulSet.
*
* @return true if the next ResultSet is valid
* @exception SQLException if a database access error occurs
*/
public boolean getMoreResults() throws SQLException
{
result = ((org.postgresql.ResultSet)result).getNext();
return (result != null && ((org.postgresql.ResultSet)result).reallyResultSet());
}
}
|
